Only two 4-halo-1
- Award ID(s):
- 1650766
- NSF-PAR ID:
- 10090752
- Date Published:
- Journal Name:
- Acta Crystallographica Section C Structural Chemistry
- Volume:
- 74
- Issue:
- 11
- ISSN:
- 2053-2296
- Page Range / eLocation ID:
- 1395 to 1402
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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H -pyrazole crystal structures are known to date (chloro and bromo, the structure of 4-iodo-1H -pyrazole has not been reported yet). The triclinic structure of 4-fluoro-1H -pyrazole, C3H3FN2(P \overline{1}), reported here is not isomorphous with those of the chloro and bromo analogues (which are isomorphous, orthorhombicPnma ). To avoid sublimation during the measurement, diffraction data were collected at 150 K. Two crystallographically unique 4-fluoro-1H -pyrazole moieties linked by an N—H...N hydrogen bond are found in the asymmetric unit. Unlike the trimeric supramolecular motifs found in the structures of the chloro and bromo analogues, 4-fluoro-1H -pyrazole forms one-dimensional chains by intermolecular hydrogen bonding in the crystal. -
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